diff --git a/.pnp.cjs b/.pnp.cjs
index f9e967e1137..98af3dfe372 100644
--- a/.pnp.cjs
+++ b/.pnp.cjs
@@ -4920,7 +4920,7 @@ const RAW_RUNTIME_STATE =
           ["@types/jest", "npm:29.5.14"],\
           ["@types/node", "npm:22.14.1"],\
           ["axios", "npm:1.13.4"],\
-          ["fastify", "npm:5.6.2"],\
+          ["fastify", "npm:5.8.5"],\
           ["nock", "npm:13.5.6"],\
           ["tslib", "npm:2.8.1"],\
           ["typescript", "patch:typescript@npm%3A5.8.3#optional!builtin<compat/typescript>::version=5.8.3&hash=5786d5"]\
@@ -5780,7 +5780,7 @@ const RAW_RUNTIME_STATE =
           ["axios", "npm:1.13.4"],\
           ["decimal.js", "npm:10.5.0"],\
           ["fast-redact", "npm:3.5.0"],\
-          ["fastify", "npm:5.6.2"],\
+          ["fastify", "npm:5.8.5"],\
           ["lodash", "npm:4.17.23"],\
           ["lru-cache", "npm:6.0.0"],\
           ["mock-socket", "npm:9.3.1"],\
diff --git a/packages/core/bootstrap/package.json b/packages/core/bootstrap/package.json
index ce96a42fd97..84e947034a2 100644
--- a/packages/core/bootstrap/package.json
+++ b/packages/core/bootstrap/package.json
@@ -21,7 +21,7 @@
     "axios": "1.13.4",
     "decimal.js": "^10.3.1",
     "fast-redact": "^3.0.1",
-    "fastify": "^5.0.0",
+    "fastify": "^5.8.5",
     "lodash": "^4.17.23",
     "lru-cache": "^6.0.0",
     "object-hash": "^2.2.0",
diff --git a/packages/sources/bank-frick/package.json b/packages/sources/bank-frick/package.json
index f4de63263f9..a1066687806 100644
--- a/packages/sources/bank-frick/package.json
+++ b/packages/sources/bank-frick/package.json
@@ -30,7 +30,7 @@
   "dependencies": {
     "@chainlink/external-adapter-framework": "2.11.6",
     "axios": "1.13.4",
-    "fastify": "^5.0.0",
+    "fastify": "^5.8.5",
     "tslib": "^2.3.1"
   },
   "devDependencies": {
diff --git a/yarn.lock b/yarn.lock
index c59aec41520..d6f096a8c3b 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2418,7 +2418,7 @@ __metadata:
     "@types/jest": "npm:^29.5.14"
     "@types/node": "npm:22.14.1"
     axios: "npm:1.13.4"
-    fastify: "npm:^5.0.0"
+    fastify: "npm:^5.8.5"
     nock: "npm:13.5.6"
     tslib: "npm:^2.3.1"
     typescript: "npm:5.8.3"
@@ -3172,7 +3172,7 @@ __metadata:
     axios: "npm:1.13.4"
     decimal.js: "npm:^10.3.1"
     fast-redact: "npm:^3.0.1"
-    fastify: "npm:^5.0.0"
+    fastify: "npm:^5.8.5"
     lodash: "npm:^4.17.23"
     lru-cache: "npm:^6.0.0"
     mock-socket: "npm:9.3.1"
@@ -13354,7 +13354,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"fastify@npm:5.6.2, fastify@npm:^5.0.0":
+"fastify@npm:5.6.2":
   version: 5.6.2
   resolution: "fastify@npm:5.6.2"
   dependencies:
@@ -13423,7 +13423,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"fastify@npm:5.8.5":
+"fastify@npm:5.8.5, fastify@npm:^5.8.5":
   version: 5.8.5
   resolution: "fastify@npm:5.8.5"
   dependencies: